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$ curl repovive.com/roadmaps/greedy-algorithms/practice-problems/minimum-deletions-implementation

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$ curl repovive.com/roadmaps/greedy-algorithms/practice-problems/minimum-deletions-implementation

Repovive

Minimum Deletions - Implementation - Practice Problems | Greedy Algorithms | Repovive

Repovive.

Greedy Algorithms8 sections · 317 units14h total

Open in Course

Minimum Deletions - Implementation

The code

Here is the solution:

function minDeletions(s)
 count := frequency map
 freqs := sorted list of frequencies descending
 used := set
 deletions := 0
 for f in freqs
 while f > 0 and f in used
 f := f - 1
 deletions := deletions + 1
 if f > 0 then
 used.add(f)
 return deletions

Time: $O(n + k^2)$ where $k$ is alphabet size. Space: $O(k)$ .

Process from highest frequency down. Each frequency is reduced until unique or gone.